Apparatus for the control of highway crossing signals



March 24, 1936. B. LAZIcH ET AL 2,035,170

APPARATUS FOR THE CONTROL HIGHWAY CROSSING SIGNALS I Original Filed Feb. 15, 1934- 2 sheets sh'eet. l

l TM IN VENT OR .5 0 Lazich a 771E119 ATTQRNE March 24, 1936.

APPARATUS FOR THE CONTROL OF HIGHWAY CROSSING SIGNALS B. LAZICH ET AL Original Filed Feb. 15, 1934 2 Sheets-Sheet 2 INVENTORS firank'oLazic/e and BY Wy yF amiiaze THEIR ATTORNEY Patented Mar. 24, 1936 UNITED STATES PATENT OFFICE APPARATUS FOR THE CONTROL OF HIGHWAY CROSSING SIGNALS of Pennsylvania Application February 15, 1934, Serial No. 3711,384 Renewed January '11, 1936 24 Claims.

'Qurinventionrelates to apparatus for the control of .highway crossingsignals, and particularly to apparatus for providing a uniform period of warning at the highway.

.Aiea'ture of our invention is the provision of apparatus, governed by .a train approaching a highway intersection, which operates to control the highway crossing signal in such .a manner that substantially an equal time of operation of the highway crossing signal before the train reaches the intersection is obtained regardless of .the speed, and which apparatus is effective than the rate of speed at which it ordinarily returns to such position. Other features and advantages of our invention will appear as the specification progresses.

We will describe one form of apparatus embodying our invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a diagrammatic view of one form of apparatus for controlling the operation of a highway crossing signal which embodies our invention. Figs. 2 and 3 are .views partly diagrammatic and partly in section of the portion of the apparatus of Fig. 1 which checks whether or not a train is accelerating. Fig. 4 is a plan view of the gear reduction assembly GB of Fig. 1, and Fig. 5 is a sectional view on the line VV of Fig. 4.

In .each of the different views like reference characters designate similar parts.

Referring to .Fig. l, the reference characters I and I designate the traffic rails of a railway over which trafiic normally moves in the direction indicated by the arrow and which rails are intersected .at grade by .a highway H shown at the right-hand end of the drawing. At the intersection there is located a highway crossing signal S. 'Thissignal S may take different forms, and is here shown conventionally as a combined audible and flashing light highway crossing signal. It will be understood, however, that our invention is not limited to this specific type of signal and any of the standard highway crossing signals may be used. .The signal S is normally inactive and is rendered active to display a warning to the highway users .whenever a. train approaches the intersection. The immediate control of the signal S is governed by a mechanism indicated by the ref- 5 erence character'FR, which mechanism is effective to cause the signal S to exhibit a warning in response to current supplied thereto.

The traffic rails l and l are divided by the usual insulated rail joints preferably into four, track sections A- B, BC, CD and DE, which track sections are traversed successively in the order namedby a train approaching the highway. Each of these track sections is provided with a track circuit comprising a track battery 2 and a trackrelay designated by the reference character R with an exponent corresponding to its location. Interposed between the track relay R and the rail 1 of the section AB is a front contact 3 of the track relay'R Interposed between the track relay .R and the rail I of the section BC is its own front contact 4, forming thereby a stick circuit for that relay over which it is normally energized. The relay R is further provided with a pickup circuit which includes a normally closed contact 55-56 of a time measuring device indicated as a whole by the reference character TM and to be described later, and a front contact 6 of the track relay R as will be understood by an inspection of Fig. 1. The function of this control for the .two track relays R and R will become apparent as thedescription proceeds.

For the purpose of this specification we shall refer .to the section AB as a measuring section, the track sections BC and CD taken together, as an operating section, and the track section D-E as a positive operating section. As will appear hereinafter, the speed, of a train as it travels over the measuring section AB is measured. Whether or not the train is accelerating is determined while the train travels the measuring section A-B and the track section BC of the operating section. The highway crossing signal S is set into operation as the train travels the operating section in accordance with the measured speed and in accordance with whether or not it is accelerating. The time of starting the operation of the signal is such that substantially an equal interval of operation before the train reaches the highway H is assured regardless of the speed of the train as long as its speed remains approximately constant, while the operation of the signal S is started as soon as the train enters the section CD if the train is accelerating. Positive operation of the signal S takes place during the time a train occupies the track section D-E irrespective of whether or not it is moving.

That the ideas may be fixed and the operation of the apparatus of our invention more readily understood, we shall assume the maximum speed for all trains to be 90 miles per hour and that twenty seconds exhibit of the highway crossing signal before the train reaches the highway is desired. A train traveling 90 miles per hour will advance approximately 2640 feet in twenty seconds. The length of the operating section, in this instance, the combined lengths of the track sections BC and CD, is preferably something greater than 2640 feet, say for example 3200 feet, in order to compensate for the usual delay in the release of the track relays and the time necessary to energize the various controlling devices. The positive operative section is preferably made short, say only 200 feet. That is, the section D-E is preferably just long enough that operation of the signal S while a train is in the immediate vicinity of the highway H whether it is moving or not is assured. That a more accurate determination of the train speed may be obtained, the measuring section is preferably made shorter than the operating section, and for reasons to appear later, it is made in this instance one-fourth the length of the operating section, namely, 800 feet in length. For the purpose of checking the train speed for acceleration, the track section BC immediately following the measuring section AB is also made 800 feet in length. It will be understood, of course, that our invention is not limited to the above lengths for the several track sections, and their lengths will be arranged to suit each individual location and to suit different maximum speeds and different intervals of operation of the highway crossing signals.

The time measuring device TM comprises a speed measuring element, an acceleration checking element and a centrifugal governor. The speed measuring element includes a shaft shown schematically by a dotted line I and four circuit controlling contact disks 8, 9, I0 and II, of suitable nonconducting material, rigidly mounted on the shaft I. The shaft I is driven by a constant speed motor M through the medium of a suitable gear reduction designated by the reference character GR. The disks 8, 9,- I0 and II normally occupy the position in which they are illustrated in the drawings, and are arranged to be at times rotated away from this normal position clockwise toward a reverse position by operating the motor M in one direction, the full reverse position being a little less than one revolution. At other times these disks are restored to the normal position by reversing the operation of the motor. The gear reduction GR may take different forms and preferably is. that disclosed and claimed in the United States Letters Patent No. 1,991,756, granted February 19, 1935, to B. Lazich, for Apparatus for changing speed and direction of rotation by reversing a constant speed motor. As the specific structure of this gear reduction forms no part of our present invention, it is shown conventionally in Fig. 1 for the sake of simplicity, and it is deemed sufiicient for this specification to point out that with the motor M rotated in the direction to drive the disks 8, 9, I0 and I I clockwise, the shaft I will be driven at the speed of one revolution per minute. When the motor is reversed and the disks driven in the counter-clockwise direction, the rate of speed will be one-fourth revolution per minute. To put it another way, these disks are rotated from the normal toward the reverse position at the rate of one revolution per minute and are rotated from the reverse position toward the normal position at the rate of one-fourth revolution per minute, the driving motor M operating at the same constant speed in both cases. The function of this change of speed for the speed measuring element will appear when the operation of the apparatus is described.

Figs. 4 and 5 disclose in detail the gear reduction GR of Fig. 1. The motor shaft I of motor M rotates at a constant speed clockwise or counter-clockwise in accordance with the direction of operation of the motor armature 61. A ratchet fits loosely on shaft I and has rigidly fastened to its hub 9| a gear 92. A second ratchet 93 fits loosely on shaft I and has rigidly fastened to its hub 94 a gear 95. A screw thread I06 is cut on the shaft I and engages a ratchet nut RN causing it to move along the axis of shaft I thereby engaging either the ratchet 90 or the ratchet 93 to drive either the gear 92 or the gear 95. The gears 92 and engage gears 96 and 91, respectively, which are fastened to the operating shaft I by pins 98 and 99, respectively. A compression spring I00 is provided in back of gear 92 and is held in place by a cup IOI pinned to shaft I by a pin I02. In like manner a compression spring I03 is provided in back of gear 95 and is held in place by a cup I04 pinned to shaft I by a pin I05. Operation of motor M in the direction corresponding to that established in response to a train occupying the measuring section AB, causes the ratchet nut RN to engage relatively low. The parts are so proportioned that shaft I is driven at one revolution per minute in response to a train in the measuring section and is driven at one-fourth revolution per minute in response to a train in the operating section.

The disks 8, 9, I0 and II are utilized for controlling the various circuits and to this end each is provided with a contact ring adapted to engage suitable stationary contact springs in the following manner. A contact ring 5| is mounted on the circumference of the disk 8and is adapted to bridge the stationary contact springs 43 and 45 at all times except at the full reverse position when the ring 5| moves out from beneath the spring 44 to open the connection between springs 43 and 44. Mounted on the circumference of the disk 9 is a contact ring 52 which is adapted to bridge the stationary contact springs 53 and 54 at all times except at the full normal position. A contact ring 51 mounted on the disk I0 is adapted to bridge the stationary contact springs 55 and 56 in the full normal position only. A contact ring 00 mounted on the disk I I is adapted to bridge the stationary contact springs 58 and 59 in the normal position and is so proportioned that the connection is broken between these two springs 58 and 59 when the disk I I has been rotated clockwise approximately five seconds. Hence, the connection between the springs 58 and 59 will be again made approximately twenty sec- 75 onds before the full normal position of the disk I I .is reached during the reverse to normal movement, it being recalled that the rate of rotation in the reverse to normal movement (counterclockwise) is only one-fourth the rate of rotation during the normal to reverse (clockwise) movement. The manner by which these several contact disks control the various circuits will also appear when the operation of the apparatus is described.

. The acceleration checking element of the device TM comprises a shaft shown schematically by the dotted line l2 and two contact disks I3 and I2 mounted thereon. The shaft I2 is driven by the constant speed motor M through the medium of a suitable train of gears indicated by a pinion l5 and a gear wheel I6. The arrangement is such that with the motor M operated in the direction to drive the disks 8, 9, H3 and II of the speed measuring element in the clockwise direction, the shaft I2 is likewise rotated clockwise and at the speed of one revolution per minute. With the motor M reversed, the shaft I2 is rotated counter-clockwise at the same speed of one revolution per minute. Hence, the rate of rotation of the shaft I2 of the acceleration checking element is one revolution per minute during both the normal to reverse and the reverse to normal operation, whereas, the shaft 1 of the speed measuring element is rotated at one revolution per minute during the normal to reverse operation and is then rotated at one-fourth revolution per minute during the reverse to normal operation.

Referring now to Figs. 2 and 3 as well as to Fig. 1, the contact disk I3 is of non-conducting material and is pinned to the shaft 12 by a pin ii and has mounted around its circumference a contact ring 8, with which a stationary contact spring IQ is adapted to make engagement. The disk I l is preferably of non-conducting material like the disk l3 but is. mounted loosely on the shaft I2. The disk M is provided with a contact ring 23, a stationary contact spring 2! being adapted to make engagement therewith. The contact ring I8 of the disk I3 is provided with a socket arrangement 22 extruding from the side of the disk I3 opposite the disk I4. The contact ring 29 of disk I4 is provided with a similar construction except in place of a socket, a pin 23 is provided which engages the socket 22 on the disk I3. It follows that at such time as the pin 23 engages the socket 22, electrical connection is completed between the rings I8 and 20, and hence between the two contact springs I9 and 2|. Fastened to the disk I4 is a ratchet wheel 24. A ratchet pawl 25 pivotally mounted at 26 is provided which engages the ratchet wheel 2%. The pressure of the ratchet pawl 25 against the ratchet wheel is adjusted by means of a compression spring 21 and a screw 28 which can be locked in position by a lock nut 29 after proper adjustment is made. The arrangement of the parts is such that when the shaft i2 is driven clockwise as viewed in Fig. l and counterl-clockwise as viewed in Fig. 3, the contact disk I3 will rotate and move the socket 22 away from the pin 23 of disk I4, the ratchet pawl 25 preventing movement of the disk I4. Consequently, the disk I3 when rotated as stated above will be effective to open the electrical connection between the two springs I9 and 2|. After the above initial operation of the disk IS a reversal of the direction of rotation of the disk I3 will bring the socket 22 back into engagement with the pin 23 and again restore electrical connection between the two springs I9 and 2|. If it is so arranged that the disk I3 is driven in the clockwise direction as viewed in Fig. l at a given'speed while a train is passing over a certain length of track section and is then reversed and driven in the opposite direction at said given speed while the train is travelling through a second track section of equal length, whether or not the train is accelerating will be determined. If the train is running at a constant speed, it will consume an equal period of time in travelling each of the two track sections and hence the socket 22 of the disk I3 will be back in engagement with the pin 23 as the train reaches the outgoing end of the second track section. If, however, the train is accelerating, it will travel the second track section in a shorter time than it required to pass over the first track section and the electrical connection between the socket 22 and the pin 23 will not be restored by the time the train reaches the outgoing end of the second track section. It is clear, therefore, that connection between the two springs I9 and 2i of the acceleration checking element of the device TM is normally closed and will be first opened and then subsequently closed in response to a train travelling at constant speed over the two aforementioned sections, and the electrical connection between these two springs will not have been closed if the train is accelerating. In the event there is deceleration of the train speed, the connection between the two springs I9 and 2I will have been closed prior to the time the train reaches the outgoing end of the second section. In this last case, the disk i3 is rotated clockwise, as viewed in Fig. 3, after the socket 22 has engaged the pin 23, and the disk I4 will be driven along with the disk I3 in the clockwise direction, the ratchet wheel 24 slipping over the ratchet pawl 25. It follows that the two disks I3 and I4 will always be in a condition for checking the acceleration of a train as it travels over the two previously mentioned track sections notwithstanding the point from which their operation will initially start may vary. The manner whereby this acceleration checking element cooperates with the speed measuring element in controlling the operation of the signal S will shortly appear.

A centrifugal governor N is operatively connected with the motor M as indicated in Fig. 1 by a dotted line 30, and this centrifugal governor controls a circuit controlling contact CI. The parts are so proportioned and adjusted that the contact CI rests in engagement with two contacts 3| and 32 as long as the motor is at rest and is lifted out of engagement therewith whenever the motor is rotated at a predetermined rate of speed. Rotation of the motor M in either direction at a rate above a predetermined value will cause the contact CI to be lifted high enough to make engagement with two contacts 35 and 34. It follows that the operating condition of the motor M is checked by the position of the contact CI.

Two relays SR and. TP are provided and serve as the medium for controlling the supply of current to the signal operating mechanism FR, the relay SR being of the usual neutral type and the relay TP being slow releasing in character. The relay SR is provided with an energizing circuit extending from the X terminal of any convenient source of current such as a battery not shown over front contact 39 of the track relay R wire 40, front contact 4! of the track relay R winding of the relay SR and thence over a front contact 42 of the track relay R to the opposite Y terminal of the current source. The relay SR is further provided with a stick circuit network comprising four separate paths over any one of which the relay may be retained energized. A first path includes the X terminal of the current source, contact 43-44 of the disk 8, wire 45, front contact 46 of the relay SR, front contact 4i, winding of relay SR and thence to the Y terminal of the current source over the front contact 42 of the track relay R A second path can be traced from the X terminal of the cur rent source over a back contact 41 of the relay TP to the wire 45 and thence as traced for the first path. A third path is traced from the X battery terminal over the contact 43-44, wire 45, front contact 46, wire 48, contact springs l9 and 2| of the acceleration checking element with the contact 22-23 closed, wire 49, winding of the relay SR and to the Y battery terminal over the front contact 42 of track relay R A fourth path extends from the X battery terminal over the back contact 41 of the relay TP to the wire 45 and thence over the same path just traced for the third path. The relay TP is energized over a simple circuit easily traced and which includes a front contact 59 by the track relay R and hence this relay TP serves as a repeater relay for the track relay R Referring to the drawings, the operation of our system can be explained in the following manner. As long as no train occupies any of the track sections, the track relays R R R and R are all picked up, relays SR and TP are energized, motor M is without current, the time measuring device TM occupies the position illustrated in Fig. l and the signal S is inactive. When a train approaching the highway H from the left enters the track section AB, the track relay R will be shunted and that relay will be released. As relay R is released, current will be supplied to the motor M, and it will be operated to drive the operating shafts l and I12 in the clockwise direction. To be explicit, the motor M will be supplied with current from the X terminal of the current source over contact 43-44, field winding 6|, wire 12, front contact 62 of the relay SR, back contact 63 of the relay R front contact 64 of the relay R wire 13, a front pole-changing contact 65 of the relay R a back pole-changing con tact 66 of the'relay R motor armature 61, a resistor 31, a second back pole-changing contact 68 of relay R and a second front pole-changing contact 69 of the relay R to the Y' terminal of the current source. The energization of the motor M by this circuit just traced is such as to cause it to rotate in the direction for driving the operating shafts l and 42 in the clockwise direction. The parts are so proportioned that the speed of the motor M will be substantially constant at a given value such that the rate of rotation of one revolution per minute for the shafts I and I2 will be obtained. This speed of the motor M will be of such value that the contact CI of the centrifugal governor'N will be lifted out of engagement with the contacts 3! and 32 but will not be raised high enough to engage the contacts 33 and 34. As soon as the disk 9 is rotated clockwise away from the normal position, the contact 53-54 will be closed and a path between the wires 12 and 13 will be completed which short circuits the path in the motor circuit including the front contact 62 of the relay SR, the back contact 63 of the relay R and the front contact 64 of the relay R After a slight movement of the disk I U,-

the connection between the springs 55 and 56 will be opened, and after approximately five seconds operation of the shaft 1 in this normal to reverse movement, the connection between the springs 58 and 59 of disk I! will be opened. Rotation of the shaft 1 2 of the acceleration checking element in the clockwise direction causes the socket 22 on the disk I3 to move out of engagement with the pin 23 and hence the connection between the two springs l9 and 2| will be broken. This operation of the last three mentioned contacts, however, performs no useful function at this time and their purpose will appear later. It follows that as the train advances through the measuring section AB, the speed measuring element and the acceleration checking element of the time measuring device will be operated in the clockwise direction at the speed of one revolution per minute. It will be noted that should the train stop in the section A-B, the circuit for the motor M will eventually be opened at the contact 43-44 when the full reverse position is reached, which position, as stated hereinbefore, is something less than one revolution, and the operation will be stopped. The shunting of the track relay R as the train enters the section A-B opens at the front contact 39 the energizing circuit for the stick relay SR, but that relay will now receive current over its stick circuit which includes the contact 43-44, its own front contact 46, and the frontcontact 4| of the relay R and it will be held energized, since this stick circuit is closed previous to the shunting of the track relay R In the event the speed measuring element is operated to its full reverse position, the above stick circuit will be opened at the contact 43-44 and the relay SR will be deenergized.

Assuming that the train advances through the measuring section A-B without stopping and enters the track section 3-0, the track relay R will be shunted and that relay will be released. The opening of the front contact 3 of the relay R causes the track relay R to be without current and to remain deenergized until such time as the'track relay R will again be picked up. With the relay R held down, the previously traced circuit for the motor M will remain closed at the back pole-changing contacts 66 and 68 of that relay the same as when the train occupied the section A-B. The track relay R upon releasing will open the front pole-changing contacts 65 and 69 and close corresponding back pole-changing contacts 16 and H with the result that the direction of the flow of current through the armature 67 of the motor M will be reversed while the direction of the flow of current through the field winding 6| will remain the same. This reversal of the direction of current flow in the armature 61 reverses the rotation of the motor, and the operating shafts I and i2 will now be driven in the counter-clockwise direction from the point to which they had advanced while the train was passing through the measuring section A-B. Due tothe gear reduction GR, the rate of rotation of the shaft 1 will be only one-fourth of a revolution per minute, but as the gear train l-l6 remains the same the rate of rotation of the shaft l2 will still be one revolution per minute. The release of the track relay R will also open the circuit to the relay TP and that relay will be released at the end of its slow-release period. The release of the repeater relay TP completes an operating circuit which makes possible the supplying of current to the mechanism FR to start operation of the signal S. This operating circuit includes two parallel paths one of which extends'from the X terminal of the current source over a. back contact 15 of the relay TP, wire 15, contact 5859 of the disk I! when bridged by the contact ring 68, wire 16, and the mechanism FR to-theopposite Y terminalof the current source. 'In parallel with the contact 58-59 is the second path extending from the wire 15 through contact CI of the centrifugal governor N in engagement with either contacts 3| and 32 or in engagement with the contacts 33 and 34 to the wire 16 and thence as before traced. Should the motor M fail to operate in the reverse direction in response to a train entering the section BC, or operate at a speed above its proper speed, the releasing of the relay I? will be effective to supply current to the mechanism FR over contact Cl and the signal S will be set into operation at once,. with the result that operation of motor'lVI is checked. The repeater relay TP being slow releasing in character, the above traced operating circuit will not be closed at the back contact 14 of. that relay until after the instant the contact CI of the centrifugal governor makes engagement with the contacts 3| and 32 as the motor" is. being reversed, and hence a flash of the signal S- as the motor M reverses will be avoided.

As stated hereinbefore, the parts are so. proportioned that the connection between the springs 58 and 59 will not be opened until the speed measuring element has been. driven. away from the normal position; for approximately five seconds. A train travelling at the maximum speed of 90 miles per hour will consume only a fraction over five seconds in passing through. the measuring section AB, and hence it will enter the section 3-0 and cause a reversal of the operation of the speed measuring element approxi mately at the same interval that the. contact 58-59 will be opened. Under this condition, this contact 5859 will be closed by the-time. the relay TP is released and current will be. supplied to the mechanism FR to start operation. of the signal S with the result that operation of the signal S during the. entire time. the train is travelling the operating section will be. obtained and the desired. twenty seconds operation of the signal before the train reaches the highway will be provided. In the event a train passes over'the measuring section at a speed less than the'maximum speed, say, for example, 60 miles per hour, it will consume approximately nine seconds before it reaches the exit end of the track section AB and its head end enters the section 3-0 with the result that the contact 58-59. will-have been opened approximately the last four seconds of this nine second period. In this case the contact 58-59 will not be closed until the disk H has been operated counter-clockwise for approximately sixteen seconds. A train travelling 60 miles per hour will consume about thirty-six seconds in passing over the operating section, and as there will be a delay of sixteen seconds in starting the operation of signal S a twenty seconds operation of the signal S before this train reaches the highway H Will be provided. An analysis of the operation of the apparatus for trains travelling at other speeds less than the maximum will disclose that approximately twenty seconds operation of the signal S before the trainreaches the highway will be obtained in each case.

After the repeater relay T1" is released, the

stick relay SR will receive current over; the: stick circuit which includes the back contact 41 of the relay TP and the front contact 4| of the track relay R. It follows that the stick relay SR will be retained energized while the train passes. over the track section BC.

It will be recalled that the track section BC is made of the same length as the track section AB, and hence for all trains advancing through these two track sections at substantially a constant speed the contact 2223 of the acceleration checking element will be reclosed as the train reaches the outgoing end of the track section BC and its head end enters the track section CD. Under'these circumstances relay SR will receive current over the stick circuit including the back contact All, front contact 46 and the conta-ct 212-425 even after the track relay R has been shunted. Consequently, for all trains having substantially a constant speed the relay SR will be retained energized while a train is in the operating section and the operating circuit for supplying current to the mechanism FR which; includes the contact 58-49 of the speed measure; ing element or the contact CI of the centrifugal It is clear, therefore, that with the motor M operating at the proper governor will be effective.

rate, the contact 58--59 of the speed measuring element will control the starting of the operation of the signal S in such a manner that substantially twenty seconds operation of the signal S before the train reaches the highway will be obtained regardless of the speed of' the train, if there is no acceleration.

We shall now consider the case where the train is accelerating as it travels over the measuring section in approaching the highway H. Under this condition, the train will require less time to travel over the track section BC than it consumed in passing over the track section AB, and, consequently, the contact 2223 of the acceleration checking element will still be open as the head end of the train enters the track section CD and shunts the track relay R The stick relay SR will now be without an energizing circuit and will be deenergized. Another operating circuit for supplying current to the mechanism FR will'now be completed from the X batteryterminal over a back contact 11' of the relay RB, a back contact 18 of the stick relay SR, mechanism FR, and to the Y battery terminal. It follows, therefore, when a train is accelerating as it moves over the measuring section, the accel eration checking element of the time measuring device is effective to prevent the delay in starting the operation of the highway crossing signal S which would be effected by the speed measuring element if the train moved through the measuring section at a constant speed, the operation of the signal being started through the medium of the auxiliary operating circuit including the back contact 78 of the stick relay SR as soon as the train enters the track section CD.

It is to be noted that the front contact 6" of the track relay R prevents the track relay- R from becoming energized while the train occupies the section CD and in turn prevents the track relay R from picking up. Consequently, the stick relay SR once deenergized in the manner described above to start operation of the signal S, that relay will remain down until the train has moved out of section CD: It" will alsobe noted that the contact 5555 ofthe disk I0 which contact is interposed in the pickup circuit of the track relay R prevents" that relay from 'relay SR and that relay is deenergized.

device TM is restored to its full normal position.

When the train advances and occupies the track section DE, the mechanism FR will receive current over another operating circuit which includes a back contact 19 of the track relay R and thus operation of the signal S as long as the train occupies the section D-E, whether the train is moving or not, is assured.

In the event a train advances into the measuring section A-B from the left and then stops, the device TM will be operated to its full reverse position, as pointed out hereinbefore. Should the train now back toward the left out of the section A B, both track relays R and R will be picked up and the motor M will be supplied with curent from the X terminal of the current source over the front contact 39 of the relay R wire 46, front contact 46 of relay SR, wire 45, field winding SI, wire 12, contact 5354, wire 13, front pole-changing contact 65 of relay R a front pole-changing contact 8!! of relay R a second front contact 8! of relay R motor armature 67, a front pole-changing contact 82 of relay R and front pole-changing contact 69 of relay R to the Y terminal of the current source. The energization of the motor M by this circuit is that which causes the motor M to be operated in a direction to rotate the shaft 1 counterclockwise. As soon as the disk 8 is rotated away from the full reverse position, the contact 43-44 is closed and from this point on the motor M will receive current through that contact until the full normal position is reached when the motor circuit will be opened at the contact 53-54. During this operation of the motor, the front contact 8! of the track relay R short circuits the resistor 31 with the result that the motor M will be operated at a very much higher rate of speed, and the time measuring device will be restored to its normal position at a speed materially faster than its normal rate. Although the contact 3334 of the centrifugal governor may be closed due to this increased rate of operation of the motor M, no operation of the signal S will cur inasmuch as the repeater relay TP is now energized.

, In the event a train is travelling in the reverse direction, that is, against the normal direction of trafiic, and enters the track section D-E from the right, the time measuring device TM will remain inactive. Under this condition, the track relay R is first deenergized to open the front contact 42 in the energizing circuit of the stick The front contact 62 of the stick relay SR being now open, the motor circuit is not completed as the track relays R R and R are shunted, and hence the device TM is not operated away from its normal position while a train travelling in the reverse direction occupies the successive track sections.

It will be further noted that in the event a train is accelerating and the stick relay SR is deenergized as the train enters the track section C-D in the manner previously described, the closing of the back contact 83 of the relay SR short circuits the resistor 31 in the motor circuit and the motor is operated at the increased rate of speed to return the time measuring device TM quickly to its normal position.

Although we have herein shown and described only one form of apparatus embodying our invention, it is understood that various changes and modifications may be made therein within the becoming reenergized until the time measuring scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim is:

1. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, a member, means governed by a train in travelling a first fixed distance in approaching the intersection for driving'said member in one direction at a given speed, means governed by the'train in travelling a second and equal fixed distance in approaching the intersection for driving said member in the opposite direction at said given speed, operating means controlled by the train for setting the signal into operation when the train reaches a fixed point, and means controlled by said member operative when said member is driven in said opposite direction a distance at least equal to the distance said member is driven in said one direction to render said operating means inelfective.

2. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, .a motor operated speed measuring device set into operation when a train approaches the intersection for starting the operation of said signal at substantially the same interval of time before the train reaches the intersection regardless of the speed of the train, amember, means governed by a train in travelling a first fixed distance in approaching the intersection for driving said member in one direction at a given speed, means governed by the train in travelling a second and equal fixed distance for driving said member in the opposite direction at said given speed, and means controlled by said member operative when said member is driven a less distance in the opposite direction than in said one direction to cancel the control of said device.

3.'In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, a motor operated speed measuring device set into operation when a train approaches the intersection for starting the operation of said signal at substantially the same interval of time before the train reaches the intersection regardless of the speed of the train, another operating means controlled by a train for setting the signal into operation when the train reaches a fixed point, a member, means governed by the train in travelling a first fixed distance in approaching the intersection for driving said member in one direction at a given speed, means governed by the train in travelling a second and equal fixed distance for driving said member in the opposite direction at said given speed, and means controlled by said member operative when said member is driven approximately an equal distance in both directions to render said other operating means ineifective.

4. Incombination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, a motor operated speed measuring device set into operation when a train approaches the intersection for starting the operation of said signal at substantially the same interval of time before the train reaches the intersection regardless of the speed of the train, a motor operated time checking device set into operation when a train approaches the intersection for comparing the time consumed by the train in travelling over two successive fixed distances of equal lengths, and means controlled by said checking device operative when the time consumed by said train in travelling the second fixed distance is less than that consumed by the train in travelling the first fixed distance to annul the control of said speed measuring device.

5. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, a motor operated speed measuring device set into operation when a train approaches the intersection Ior starting the operation of said signal at substantially the same interval of time before the train reaches the intersection regardless of the speed of the-train, another operating means controlled by a train for setting the signal intooperation when the train reaches a fixed point, a motor operated time checking device set into operation when a train approaches the intersection for comparing the time consumed by the train in travelling over twosuccessive fixed distances of equal lengths, and means controlled by said checking device operative when the time consumed by said train in travelling the distances is approximately equal to render said other operating means ineffective.

6. In combination, a stretch of railway track, a signal located along the stretch, two successive track sections of approximately equal lengths, an operating circuit controlled by a train for governing saidsignal, an acceleration checking device controlled by a train set into operation when a. train enters the first of said sections for comparing the time consumed by the train in travelling over said two track sections, and means controlled by said checking device operative when the time consumed in the two sections is approximately equal to render said operating circuit ineffective.

'7. In combination, a stretch of railway track, a signal located along the stretch, two successive track sections of approximately equal lengths, twooperating circuits for controlling said signal and both normally inactive, a time measuring device controlled by a train set into operation when a train enters the first of said sections for measuring the time consumed by the trainin travelling over each of said two track sections; means controlled by said device operative to render one of said operating circuits active in accordance with the time consumed in travelling the first of said sections, and means controlled by said device operative when the time consumed by said train in travelling the second of said sections is less than that consumed by the train in travelling the first of said sections to render the other of said circuits active.

8. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection; a first, a second and a third track section over which a train successively passes in approaching said highway, said first and second track sections being of approximately equal lengths; at'rack circuit for each section including a track relay, one operating means for operating said signal by deenergizing the track relay of the second section, another operating means for operating the signal by deenergizing the track relay of the third section, a speed measuring device set into operation by deenergizing the track relay of the first section for delaying said one operating means in starting operation of the signal according to the speed of the train, a member, means for driving the member in one direction at a given speed operative upon the deenergizing of the relay of the-first section, means for driving the member in the oppositedirection at said given speed operative upon the deenergizing of the relay of the second section, and means controlled by said member for governing said other operating means according to the distances said member is-driven.

9'. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, operating means for setting the signal into operation when a'train approaching the intersection reaches a fixed point, a first device controlled by the train to register the speed of the train as it approaches said fixed point and efiective to delay the operat'ing means in setting the signal into operation for aperiod determined by the registered speed, a second device governed by the train as it travels a given distance in approaching the fixed point and an'equal distance as it recedes from said point to determine whether or not the train is accelerating, and means governed by the second device effective to cancel the control of the first device if acceleration is registered.

10. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, a first and a second track section over which a train successively passes in aproaching the highway and each of which is provided with a track relay, a time measuring device comprising a member normally occupying one position and an electric motor arranged to move said member away from said one position in response to rotation of said motor in one direction and to restore said member to said one position inresponse torotation of said motor in the opposite direction, a first circuit means including a back contact of the track relay of said first section effective for energizing said motor in such manner that said motor is rotated in said one direction at a given constant speed, a second circuit means including a back contact of the track relay of the second section effective for energizing the motor in such manner that said motor is rotated in said opposite direction at said given constant speed, a first operating means controlled by said memberand responsive to its position away from said one position for determining the time of starting operation of said signal, astick relay controlled jointly by the track relays of said sections and a contact responsive to the time said motor is rotated in the two directions respectively, and a second operating means for starting operation of said signal ineluding a back contact of said stick relay.

11. In combination, a stretch of railway track in ersected by a highway, a highway crossing signal located-at the'intersection, a time measuring device comprising a member normally occupying one position and an electric motor arranged tomove said member away from said one position in response to rotation of said motor in one direction and to restore said member to said one position in response to rotation of said motor in the opposite direction, a first circuit means effective when a train approaching said highway passes a first fixed point for energizing said motcr'in such manner that said motor'is rotated in said one direction at a given constant speed, a second circuit means including a resistor effective when the train passes a second fixed point for energizing the motor in such manner that said motor is rotated in said opposite direction at said given constant speed, means controlled by said member and responsive to its position away from said one position for determining th time,

of starting operation of said signal, and trafiic controlled means effective at times to short-circuit said resistor for causing said motor to rotate in said opposite direction at a speed higher than said given constant speed for causing a quick return of the member to said one position.

12. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, a first and a second track section over which a train successively passes in approaching the highway and each of which is provided with a track relay, a time measuring device comprising a member normally occupying one position and an electric motor arranged to move said member away from said one position in response to rotation of said motor in one direction and to restore said member to said one position in response to rotation of said motor in the opposite direction, a first circuit means including a back contact of the track relay of said first section and a resistor efiective for energizing said motor in such manner that said motor is rotated in said one direction at a given constant speed, a second circuit means including a back contact of the track relay of the second section and said resistor effective for energizing the motor in such manner that said motor is rotated in said opposite direction at said given constant speed, means controlled by said member and responsive to its position away from said one position for determining the time of starting operation of said signal, and a third circuit means efiective at times for energizing the motor in such manner that said motor is rotated in said opposite direction and including a front contact of the track relay of the first section for short-circuiting said resistor whereby said motor is rotated at a speed higher than said given constant speed and the member quickly returned to said one position.

13. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, a first and a second track section over which a train successively passes in approaching the highway and each of which is provided with a track relay, a time measuring device comprising a member normally occupying one position and an electric motor arranged to move said member away from said one position in response to rotation of said motor in one direction and to restore said member to said one position in response to rotation of said motor in the opposite direction, a first circuit means including a back contact of the track relay of said first section and a resistor effective for energizing said motor in such manner that said motor is rotated in said one direction at a given constant speed, a second circuit means including a back contact of the track relay of the second section and said resistor effective for energizing the motor in such manner that said motor is rotated in said opposite direction at said given constant speed, a first operating means controlled by said member and responsive to its position away from said one position for determining the time of starting operation of said signal, a stick relay controlled jointly by a train approaching the intersection and a contact responsive to the time said motor is rotated in the two directions, a second operating means for starting operation of said signal including a back contact of the stick relay, and a third circuit means effective at times for energizing the motor in such manner that said motor is rotated in said opposite direction and including a back contact of the stick relay for short-circuiting said resistor whereby said motor is rotated at a speedhigher than said given constant speed and the member quickly returned to said one position.

14. In combination, a stretch of railway track intersected by a highway, at highway crossing signal located at the intersection, a first and a second track section over which a train successively passes in approaching the highway, a track relay for each section responsive to trafiic conditions of the section, a time measuring device comprising a member normally occupying one position and an electric motor arranged to at times move said member away from said one position and at other times to restore said member to said one position, a first circuit including a back contact of the track relay of said first section effective for energizing said motor in such manner as to move the member away from said one position, a second circuit including a back contact of the track relay of the second section efiective for energizing said motor in such manner as to restore the member to said one position, operating means governed by the track relay of the second section when deenergized effective to set the signal into operation, means controlled by said member responsive to its position away from said one position for determining the time of starting operation of said signal, and circuit means for energizing the track relay of the second section when the train vacates said second section including a contact controlled by said member and closed when and only when said member occupies said one position.

15. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection, two track sections of approximately equal lengths which a train successively travels in approaching the intersection, two operating circuits for setting said signal into operation, a first and a second member, means set into'operation when a train enters the first of said sections for driving said members in one direction while the train is passing over said first section, means set into operation when a train enters the second section for driving said members in the opposite direction while the train is passing over the second section, means controlled by said first member operative to control one of said circuits in accordance with the distance said first member is driven in said one direction, and means controlled by said second member operative to control the other of said circuits in accordance with the difference between the distance said second member is driven in said one direction and the distance the member is driven in said opposite direction.

16. In combination, a stretch of railway track intersected by a highway and formed into a relatively short measuring section and a relatively long operating section on one side of the highway, a highway crossing signal located at the intersection, a slow acting device, means governed by a train occupying the measuring section for operating said device and including a first gear reduction, means governed by a train occupying the operating section for operating said device and including a second gear reduction, said first and second gear reductions having a ratio with respect to each other which is inversely the same ratio as the length of the measuring section to the length of the operating section, and operating circuit means governed by said slow acting device for setting said signal into operation.

, 1'7. In combination, a stretch of'railway track intersected by a highway and formed with an operating section on one side of the highway having a length which requires a predetermined interval for a train moving at a given maximum speed to travel therethrough, a measuringsection located adjacent the operating section remote from the highway and arranged relatively short in length, a highway crossing signal located adjacent the intersection, a slow acting device, motor operating means for actuating said device and including a first and a second gear reduction, said first and second gear reductions having a gear ratio with respect to each other which .is inversely the same ratio as the length of the measuring section to the length of the operating section, a first circuit governed by a train occupying the measuring section for causing said motor to actuate said device through the first gear reduction, a second circuit governed by a train occupying the operating section for causing said motor to actuate said device through the second gear reduction, and an operating circuit controlled by said device for setting the signal into operation substantially the same interval before the train reaches the highway regard less of the speed of the train.

18. In combination, a stretch of railway track intersected by a highway and formed into a measuring section and an operating section on one side of the highway, said measuring section arranged relatively short in length compared with the length of the operating section, a highway crossing signal located at the intersection, a time measuring device including a member having a normal position and adapted to be moved away from its normal position toward a reverse position and to be moved back toward the normal position, means governed by a train when occupying the measuring section to operate said device for moving said member away from the normal position and including a first gear reduction, means governed by a train when occupying the operating section to operate said device for moving said member back toward the normal position and including a second gear reduction, said first and second gear reductions having a gear ratio with respect to each other which is inversely the same ratio as the length of the measuring section to the length of the operating section, and operating means governed by said member for setting said signal into operation.

19. In combination, a stretch of railway track formed into a measuring section and an operating section, said measuring section being relatively short with respect to the operating section, a constant speed motor, control means for operating said motor in one direction in response to a train traveling the measuring section and to operate the motor in the reverse direction in response to a train traveling the operating section, a shaft capable of being reversibly rotated, a first gear train having a relatively high gear ratio, a second gear train having a relatively low gear ratio, means eifective to rotate the shaft in one direction through said first gear train when the motor is operated in its said one direction and effective to rotate the shaft in the reverse direction through said second gear train when the motor is operated in its said reverse direction whereby the shaft is rotated in one direction at a relatively high speed when a train occupies the measuring section and is rotated in the reverse direction at a relatively low speed when a train occupies the operating section, and time measuring means operatively connected with the shaft and including a circuit controlling. contact. o

20. In combination, a stretch of railway track formed into a measuring section and an operating section, said measuring section being relatively short with respect to the operating section, a constant speed motor, control means for operating said motor in one direction in response to a train traveling the measuring section and to operate the motor in the reverse direction in response to a train traveling the operating section, a shaft capable of being reversibly rotated, a first gear train connected with the shaft and having a relatively high gear ratio, a second gear train connected with the shaft and having a relatively low gear ratio, coupling means governed by the direction of rotation of said motor and effective to drive said first gear train when the motor is operated in its said one direction and to drive said second gear train when the motor is operated in said reverse direction whereby the shaft is rotated in one direction at a relatively high speed when a train occupies the measuring section and is rotated in the reverse direction at a relatively low speed when a train occupies the operating section, and time measuring means operatively connected with the shaft and including a circuit controlling contact.

21. In combination, a stretch of railway track intersected by a highway and formed into a measuring section and an operating section on one side of the highway, said measuring section being relatively short with respect to the operating section, a highway crossing signal located at the intersection, a constant speed motor, control means for operating said motor in one direction in response to a train traveling the measuring section and to operate the motor in the reverse direction in response to a train traveling the operating section, a shaft capable of being reversibly rotated, a first gear train connected with the shaft and having a relatively high gear ratio, a second gear train connected with the shaft and having a relatively low gear ratio, coupling means governed by the direction of rotation of said motor and effective to drive said first gear train when the motor is operated in its said one direction and to drive said second gear train when the motor is operated in its said reverse direction whereby the shaft is rotated in one direction at a relatively high speed when a train occupies the measuring section and is rotated in the reverse direction at a relatively low speed when a train occupies the operating section, and time measuring means including a circuit controlling contact operatively connected with the shaft for governing the operation of said signal.

22. In combination, a stretch of railway track intersected by a highway and formed into a measuring section and an operating section on one side of the highway, said measuring section being relatively short with respect to the operating section, a highway crossing signal located at the intersection, a constant speed motor, control means for operating said motor in one direction in response to a train traveling the measuring section and to operate the motor in the reverse directionin response to a train traveling the operating section, a shaft capable of being reversibly rotated, .a first gear train connected with the shaft and having a relatively high gear ratio, a second gear train connected with the shaft and having a relatively low gear ratio, coupling means effective to drive said first gear train when the motor is operated in its said one direction in response to a train occupying the measuring section and to drive said second gear train when the motor is operated in its said reverse direction in response to a train occupying the operating section, and time measuring means including a circuit controlling contact operatively connected with the shaft for governing the operation of said signal.

23. In combination, a stretch of railway track intersected by a highway and formed into a measuring section and an operating section on one side of the highway, a highway crossing signal located at the intersection, a shaft having mounted thereon a circuit controlling contact which is adapted to be set at a given normal position, a first and a second gear train, a motor, means controlled by a train occupying the measuring track section to operate the motor in one direction to drive the shaft through the first gear train for moving said contact away from its normal position, other means controlled by a train occupying the operating track section to operate the motor in the other direction to drive the shaft through the second gear train for moving said contact toward its normal position, and circuit means controlled by said contact for governing said signal.

24; In combination, a stretch of railway track intersected by a highway and formed into a measuring section and an operating section on one side of the highway, a highway crossing signal located at the intersection, a constant speed motor having a given speed, control means for operating said motor in one direction in response to a train occupying the measuring section and in the oppo site direction in response to a train occupying the operating section, a shaft, a first gear train connected to said shaft and capable when driven at said given speed of rotating said shaft atv a relatively high speed, a second gear train connected to said shaft and capable when driven at said given speed of rotating said shaft at a relatively low speed, coupling means governed by the direction of rotation of said motor for selectively driving said first or said second gear train whereby said shaft is rotated in one direction at a relatively high speed when a train is traveling the measuring section and is rotated in the opposite direction at relatively low speed when a train is traveling the operating section, and a circuit controlling contact operatively connected with said shaft for governing said signal.

BRANKO LAZICH. HENRY J ZYGMUNT. 

